Doug Lord

Radio Control Multihulls

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The graph shows propeller rpm and the voltage and current from one 6 cell battery pack.

 

Very impressive. Thanks for sharing

 

If I'm honest I was expecting to see more amps!

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Do you have any experience with the Lithium Ferrite(LiFE) batteries. I was told they have safer characteristics in terms of mishandling than the LiPO batteries-any info?

 

https://www.youtube.com/watch?v=Vf2LlZPy3GM

 

This shows a deliberate short circuit test & the insulated wire produces a lot of smoke but there's no internal thermal runaway that results in fire. I've seen cells intentionally damaged (a nail driven through the cell) & subsequently run without issue. Below is a Googled MSDS

 

http://www.siomar.com/userfiles/file/Lithium%20Rechargeable/LITHIUM%20IRON%20PHOSPHATE/Lithium%20Iron%20Phosphate%20MSDS_LiFePO4.pdf

 

The only considerations in my view are the lower nominal voltage & lower energy density per gram - but the latter may have changed recently. I've used LiPo almost exclusively for the last 24 months which is a long time in terms of lithium battery development!

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"If I'm honest I was expecting to see more amps!"

 

At the time we ran the boat (2008), 20C batteries were state of the art. We could have pulled 200 amps from the batteries if we didn't care about life, but the motor was getting hot as it was. Seventy horsepower was more than this hull runs with IC engines. We were running the boat too fast for the design and it showed signs of instability. When we started the project, we only expected to run 80 mph.

 

I have no experience with LiFe batteries since thay have lower performance for our power applications. I run lithium polymer receiver batteries and have had no problems with that gentle application.

 

:Lohring Miller

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imaxit why don't you fuck off and stop filling decent threads with whatever it is you are pushing.

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The cat above was really foiling. Not stable, not too much but even much better than on the small video.

Here's an update of my tri. Not foiling but with a wing, standard rig and tons of fun!

 

Top speed was 8,7 knots, length is 1,2 meter, wind was around 15kn. Cheers Chris

 

 



some more action is here

 

post-51057-0-21632100-1365974881_thumb.jpg

post-51057-0-57194000-1365974893_thumb.jpg

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Hi Doug, yes the flap is removed for reefing. I had a small "igotu" tracker on the boat. Received some helpful data...

 

 

post-51057-0-16108200-1365977129_thumb.jpg

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Doug, i use 4 chanels.

one for the main cheat

one for the flap control aprox. +- 30 degr AoA

one for the ruder

and one for the up and down control of the daggerboards / foils

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H, how do you adjust the angle of incidence of the foils? Do you ever have to do that under sail?

Doug, i can´t adjust the angel of incidence of the foils under sail now. I"ll do it later on (plan B) B)

Actual i can just adjust it with a screw/bolt and a sliding plate at the leading adge of the foil slot.

I fix it befor starting. The angel of incidence is est. 4-5 deg.

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Doug you do realize that since the end of March the only one who has responded to your posts is a newbie who's never posted in SA before and doesn't know any better right?

 

Aren't you the least bit embarassed by presenting 20 year old projects as though they are recent ones?

 

Frankly if I said my model boat was probably going to be sailing in 2 mos and instead its going into the paint shop after more than a month of zero progress, I'd probably feel I have some 'splaining to do.

 

 

Hydroptere, its cool that you've actually built the thing that Doug wishes he had. But I strongly recommend that you take most of what he says with a grain of salt. His "foiler" that he just described and showed pictures of is a 20 or so year old project that never actually flew on foils and that he abandoned very quickly.

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Doug - do you really not get how sad it is for a man your age to be touting things you did 15 years ago? From age 12-age 18 I built probably a dozen airplanes (1/2 of them RC) and 4 boats all the while also being active in lots of other clubs and being on two sports teams.

 

Seriously dude, you aren't married, you don't have kids... Is this really the best you can do?

 

PLEASE PLEASE PLEASE go out and do something real.

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Doug - do you really not get how sad it is for a man your age to be touting things you did 15 years ago? From age 12-age 18 I built probably a dozen airplanes (1/2 of them RC) and 4 boats all the while also being active in lots of other clubs and being on two sports teams.

 

Seriously dude, you aren't married, you don't have kids... Is this really the best you can do?

 

PLEASE PLEASE PLEASE go out and do something real.

I'm 70 years old and also built model airplanes as a teenager. I still build and race radio controlled model boats. Along the way I sailed a variety of boats including Lightnings, Thistles, Coronado 15s, and Class C catamarans. In the late 1960's I worked in the engineering department of General Dynamics Electric Boat Division. I promise that they did model testing. I've been involved with designing the

. We built a model to test various ideas before committing to the full scale design. Models are a time tested way to try new things without spending lots of time and money. The complex interactions in sail boats are hard to predict, even today. If you aren't an America's Cup team with millions of dollars to spend on engineers and computer programs, models are a great, low cost method.

 

By the way, Burt Rutan won model airplane contests as a teenager. He went on to test radical airplane concepts using a model mounted on a pickup. Take a look at the Scale Composite web site to see what a model builder can accomplish. For those of us for whom aerodynamics isn't our day job, model building is a great way to explore the science. Too bad you grew out of your curiosity and interest in exploring new ideas.

 

Lohring Miller

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Lohring, I think Baltics post was spot on. We here haven't lost our curiosity we have lost patience with the Lord and his on again off again projects. Right now Doug has at least 2 projects going. Over on Boat design.net one has generated over 400 posts but has yet to move. And the original design brief has been modified so many times many have lost what the concept was. His other project keeps turning up here, every 2 years or so but has yet to make any forward progress. Lack of funding seems to have shelved that one for now despite several idea of how he could get the funding. Doug has big ideas that might turn out to be something. People are just tired of his lack of progress. This tri, the one that just got painted red, has been kicked around here for several years, and it's only a model.

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On target post, ZTH.

 

I think that most reasonable people see that there is a degree of validity to the construction of a model as it might apply to larger scale efforts. It's done all the time to help flesh out conceptual efforts and nobody that I know would discount the potential. What ZTH says about the crew here and over at bd.net being tired of the incessant postings that say, basically, the very same things over and over with no development in a physical way... well it's gotten to the point where it's truly boring.

 

Enough already, just put a sock in it and build the damn thing and prove that it works... and this isn't about the real goal which is to actually build a full-size working design. Without any completion, and there seems to be an endless stream of excuses that prevent that, this has become what amounts to a free-association therapy session with no possibility for a conclusion.

 

Take a few hours of your time to page around over at Boatdesign.net and look at the endless threads posted by Mr. Lord. Threads in which he is the overwhelming volume contributor, sometimes as much as 85%+ of the posts, and you'll see what we mean by this position.

 

Bottom line is this... when someone flails about on the forums, boasting about his incredible vision and how his contraption is going to create a new understanding of foiling boats, then spends thousands of hours building the thing at the cost of more thousands of dollars, would you not expect that there would be some serious photography and video of this incredible machine doing its foiling thing so they can prove that their idea worked?

 

And when someone completes their initial successful tests, why would they take the boat apart and give away the primary hull to a windsurf school so that they can use it for beginner training sessions? And lastly, why in the hell would they go about on the various fora, spewing as loudly as they can about their great accomplishment; which they can't prove, doesn't exist anymore and is only as good as their flakey word?

 

That's but one instance as to why people are on this guy's case to get a product built and demonstrated, rather than fill more bandwidth with hot air.

 

.

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I think it didn't bind because it's so thin it can still form the shape it needs even deflected under load.

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Doug - do you really not get how sad it is for a man your age to be touting things you did 15 years ago? From age 12-age 18 I built probably a dozen airplanes (1/2 of them RC) and 4 boats all the while also being active in lots of other clubs and being on two sports teams.

 

Seriously dude, you aren't married, you don't have kids... Is this really the best you can do?

 

PLEASE PLEASE PLEASE go out and do something real.

I'm 70 years old and also built model airplanes as a teenager. I still build and race radio controlled model boats. Along the way I sailed a variety of boats including Lightnings, Thistles, Coronado 15s, and Class C catamarans. In the late 1960's I worked in the engineering department of General Dynamics Electric Boat Division. I promise that they did model testing. I've been involved with designing the

. We built a model to test various ideas before committing to the full scale design. Models are a time tested way to try new things without spending lots of time and money. The complex interactions in sail boats are hard to predict, even today. If you aren't an America's Cup team with millions of dollars to spend on engineers and computer programs, models are a great, low cost method.

 

By the way, Burt Rutan won model airplane contests as a teenager. He went on to test radical airplane concepts using a model mounted on a pickup. Take a look at the Scale Composite web site to see what a model builder can accomplish. For those of us for whom aerodynamics isn't our day job, model building is a great way to explore the science. Too bad you grew out of your curiosity and interest in exploring new ideas.

 

Lohring Miller

Lohring, Models ARE a time tested way to try things out before building to scale. The gotcha is that

 

1) for that claim to be meaningful you gotta eventually build to scale - Doug has not in 20+ years

 

2) because the world is non-linear, your scaling function has to take that into account, Doug's never have

 

 

I realize that not every 70yo can have the fortune to be able to continue racing little quirky boats at that age - though some do. But Doug isn't 70. The reason Doug hasn't sailed anything in the last 20 years physically is not for lack of access or boats (he still has the hull of his 20+yo abomination) but he has let himself become physically unfit enough to do so. And rather than try and address that aspect, he keeps building models that he claims he will scale up but never does because he quickly realizes that he could not sail it if it got built.

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What did I tell you, Lohring?

 

This is the same crap we've all seen a dozen, or more, times already and yet, here it is, once again.

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My test model trimaran was started in 2010 and is nearly finished. If you're interested in the facts relating to the history of this boat check out the thread here: http://www.boatdesign.net/forums/multihulls/high-performance-mpx-foil-self-righting-trimaran-test-model-36058-27.html

The boat is precisely scaled down from the 18' design-3.33" to the foot. SA and weight are somewhat wide open for testing but can be evaluated using the formula: SA varies as the square of length and displ./weight varies as the cube of length. All this is covered in the thread in great detail. When the project started the idea was to test a self-righting trimaran concept. It still is, but the priority for testing is the revolutionary foil system that will allow the main hull to fly in light air while utilizing the oversquare platform to the max in the strongest wind. This foil system, if it works, should be ideal for small, high performance trimarans from 12' on up. Just for the record-there is no such thing as a "high performance trimaran" 12' long anywhere today. The reason is because it will take a foil system similar to the one on the test model to achieve such a small, very cool trimaran.

 

Below -pictures of a 12' concept model using this foil system with planing hulls. L to R, 1& 2 showing the retractable gantry and sliding bench seats(not on 18) but ideal for the 12, 3&4- the ama + curved piece-similar on the 18 allows great reserve buoyancy with low high speed wave/water immersion drag, shows the planing ama+ foil assist-a variation of this system is on the Test Model,

5- A mocked up rig :

12 foot? That looks like 12 inches

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Doug how much are you spending on the sails for the bigger model? You are having a set made right? How much is this model going to cost? Why not put that $ into a full size boat?

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... If the system works it will change small, high performance trimaran design for good...

 

It will do nothing of the kind. What a self-centered, preposterous pile of baloney.

 

Even if it does work, which is not a very high percentage play, it only proves that this particular application will work and has no bearing on other configurations, sizes, or purposes. It's an extreme one-off, so let's not get ahead ourselves on the counting of the chickens thing. A prudent, reasoned designer would never say this kind of thing long before they have a scale model in the water.

 

First thing that has to happen... Doug has to prove that he can actually complete a project and get it to work. Show it working on video for more than a split second at a real time playback and document the living crap out of the test with still photos from several angles. Well down the line somewhere in the very far away future, is a place where other thoughts MIGHT be on the table.

 

Pure, Fantasyland Hokum.

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What I find curious is the shape of the main hull. It completely ignores all modern knowledge of either planing hulls (it has a relatively high prismatic quite far aft) or multi-hulls ((21:1 beam to length for optimal efficiency).

 

So Chris, I think Doug is in fact right about one thing. if this model REALLY REALLY works, (according to the criteria you describe) it will radically change how tris are designed.

 

Because

 

  • he will have shown that having a radical shift in CLR as you go from immersed Vaka to flying Vaka ... does not matter
  • that inability to move weight fore/aft Does not matter
  • that a lifting foil in the Vaka works better than lifting foils in the Amas - something DogZilla was unable to sort out
  • The Warhammer Orc Red http://www.totalwargamer.co.uk/blog/wp-content/uploads/2011/02/orcs-and-goblins-army-book-2011.jpg is in fact faster than Mini/Volvo Orange
  • that 21:1 optimal beam to length ratios of the Gugeons, the Dogzillas, the Tornados, the F18s are all wrong

     

     

 

 

If all that in fact manages to "be successful" (as in work better than a simple Hobie 18 or Nacra 20 ) he will in fact revolutionize the industry

 

(3 years to build a model Doug? Seriously? WOW!!)

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Doug, just curious, this foil system, do you have a patent or any sort of intellectual property protection on it? You are putting a lot of info out on the net and if you were hoping to make a good amount of $ (provided it works) you may have a very difficult time now.

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Doug used to put a lot of credence and personal emotion into the whole stinking pile that is "having one's stuff patented" Truth is, a patent is a dandy thing to hang on one's wall for the buddies to come over and oooh and ahhh about, but when it comes to the actual function of owning a patent, there is one simple truth: A patent is only as good as your willingness to protect it in court.

Since Douglas is decidedly broke these days. (Why else would it take three years to build a model boat?) There's absolutely no chance that he is going to waste his limited cash, writing and illustrating a patent, having an attorney review it and then filing the thing. There's even less chance that he could mount a court case to functionally defend this new patent should someone with means bogart his idea... If it is original.

 

Nope, he's at a dead end with the patent game.

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If you Google Doug Lord and in patents,, you will find a bunch of them. But they are all problematic in that they don't adequately deal with "prior art" - they DO give you an idea of what Doug was working on when. Frankly there isn't much patentable in Doug's foil system and it isn't nearly as unique as he claims it to be.

 

See that's the gotcha here. Always has been.

 

Look I hope Doug enjoys his model. but $3k for an RC model? Wow!!!

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BTW I suspect that Hugh would have a slightly different version of the conversation. Shall we ask him?

 

As for your hull being "narrower" than a Weta, That has no bearing on the really wackadoodle prismatic shape, Nor is the Weta anything but a compromise for the mass market.

 

Hmm lets go ask Hugh shall we?

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I discussed the whole concept in detail with Hugh Welbourn when he visited me and he thought it would work and was a very innovative idea. Can't get much better encouragement than that.

 

Well, heck yeah, Doug. A guy can't get much better in the multihull design world than that.

 

Douglas, with that statement, you just moved Hugh right on past VPLP, Nigel Irens, Benoit Cabaret, Morelli-Melvin, Jim Antrim, Tim Clissold, while Hugh is having words put in his mouth, approving small foiling multihulls that will, how'd you say it... "change small, high performance trimaran design for good..." That's an incredibly tall order for a bunch of funky sketches and a, still unfinished, scale model.

 

I wonder now, if Hugh, who comes across as a really balanced and genuine kind of guy, would find this embarrassing as hell. I wouldn't be surprised if he now regrets having taken the time to listen to you.

 

Damn, Doug, is there no pile of BS too high for you to toss at a topic in order to make yourself out to be some kind of important dude?

 

Tinho Dornellas... remember that lovely fiasco where you BS'd a storm of lies about how he won the Windsurfing World Championship so that his acquaintance-level relationship with you would seem to put you in a rarified world of folks who accomplish something? When Tinho was invited to come speak to that at bd.net, he had to clear the air and tell everyone that he was not a World Champion and that it was improper for anyone to refer to him in that fashion.

 

Douglas. Make your own destiny and keep your grubby mitts off the coat tails of those who have.

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BTW I suspect that Hugh would have a slightly different version of the conversation. Shall we ask him?

 

As for your hull being "narrower" than a Weta, That has no bearing on the really wackadoodle prismatic shape, Nor is the Weta anything but a compromise for the mass market.

 

Hmm lets go ask Hugh shall we?

 

One time only post...

 

Give it a rest guys - I saw what Doug was working on and the thought process behind it, liked the logic, and good for him for trying it out it practice. If people didn't try things we'd still be floating around on rafts. Not everything works, but we keep trying.

 

If you want to have a crack at me then fine but have the decency to do it direct - however please note I've done quite a bit of work with Nigel on assorted projects in past, and we both used to live on boats on the Hamble at the same time last century so we go back a long way. Multihulls are not foreign country to me either in design or sailing capacities, but my own design and sailing interests happen to lie elsewhere.

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...I saw what Doug was working on and the thought process behind it, liked the logic, and good for him for trying it out it practice. If people didn't try things we'd still be floating around on rafts. Not everything works, but we keep trying.

 

If you want to have a crack at me then fine but have the decency to do it direct - however please note I've done quite a bit of work with Nigel on assorted projects in past... Multihulls are not foreign country to me either in design or sailing capacities, but my own design and sailing interests happen to lie elsewhere.

 

First of all, nobody is having a crack at you, personally. I thoroughly enjoy and respect your contributions to sailing through your design work. I don't think it's too difficult, though, to say that your work has not focused on multihulls and especially, foiling multihulls, in the way that Nigel, VPLP, Antrim, et. al. have throughout their careers. That's not a shot at you. It's just fact. Yet, Doug is hoisting you into the multihull foiling design firmament with comments like, "(with this endorsement) you can't get much better than that."

 

Similarly, nobody had a crack at Julian Bethwaite when Doug shared that Julian supported his (Doug's) wacky idea of a 60' plus monohull with supersonic, on-deck, moving ballast. According to Doug, Bethwaite endorsed his project because he said the concept had potential. Nothing more than that was uttered. Doug, back then, was on one of his tears around the world spouting off about how the world of sailing would change when his idea for an outrageous design would shred the sensibilities of sailing forever. He predicted the end of multihulls as the fastest boats on the water and insisted that expensive, complicated devices with huge degrees of danger to the crew on board would be the way to go... all on the back of one simple comment from Julian.

 

In my previous post above, I briefly indicated how Doug mounted a campaign of erroneous "facts" about a completely innocent guy, Tinho Dornellas, referring to him as a World Champion so that Doug could, once again, find himself in the company of greatness and associate that fabricated company as something that gave him substance.

 

Now, he's doing it AGAIN, with you as the figurine on top of his god awful cake of overly complex systems and a model that has taken three years to get to a place where it still isn't ready to hit the water. Yet, the incessant blabbing about how it "will change small, high performance trimaran design for good..." is still on his lips. Really, Hugh, this is the type of fellow with whom you wish to have your name associated?

 

As best as I can recall... Nobody that I have ever seen on any of the Internet locations where this model of his has been displayed and talked about, has tried to discourage him from doing so. They have urged him to get it done, or to turn down the rhetoric and hype until he proves that it would work... all to no avail, of course. But, nobody is telling him he can't do it. Likewise, nobody is saying that discovery of new ideas is a worthless process, or that experimentation is wrong. Doug has always been free to fiddle all he wants and produce whatever Rube Goldbergian devices he see fit to fabricate. The rub comes when he runs out of ideas to hype and has to resort to hoisting non-endorsements to the rafters, as if folks with credentials are approving his every move and in one instance, even give someone a credential which they never achieved.

 

Nobody had a crack at Eric Sponberg, who is a really great person and very accomplished NA in Florida, who used to be associated with Doug publicly. Once upon a time, he even posted to some of Doug's threads over on Boatdesign.net. Now, Doug only alludes to an engineer of high repute when he talks of his projects and how the work would be checked for technical accuracy and no mention of Eric's name appears anywhere. That's kind of curious to me, when Sponberg used to be one of those guys that Doug mentioned like he mentions your name, Hugh.

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Hey Doug,

just keep it up and get us updated. And Chris, if you critizise Doug for not delivering any practical evidence on new multihulls - why don't you just reduce your own post to just such posts.

 

Thanks

 

Chris (another one)

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... And Chris, if you critizise Doug for not delivering any practical evidence on new multihulls - why don't you just reduce your own post to just such posts.

 

Chris (another one)

 

That strategy has been tried with Doug, along with something like fifty others over the years. He has no limits, no manners and no sense of being a fool. So thoughtful, well regulated commentary won't work on him. When someone refuses to acknowledge the opinions of others, calls them names, suggests that they are stupid, uninformed, absurd, silly, and a whole litany of suggestive phrases designed to amp-up the discourse without also carrying any substance then there's only one play left. When that same someone causes a whole slice of the sailing community to leave the forum in droves (Moth Foilers) I find that distasteful and a real hammer to the overall community. This same guy is now in the process of doing the same thing to the A-Cat Class of sailors, who are growing very tired of the relentless nonsense from this person.

 

The guy suggests procedures and solutions that carry with them real danger to the sailors who are naïve enough to fall for his pseudo knowledge base. Now, maybe you don't, but I, for one, see that as a threat to the whole community and its well-being. If Doug kept his spew to himself and slaved away with his answer to what ails the sailing industry in private, I wouldn't have anything to say. Unfortunately, he brings it to a public access forum and now it is open to whatever kinds of comments that fit.

 

I tell you what, you try to reason with the guy. You tell him that his past is still on the minds of all the forum members and that he's doing the same BS stuff to the A-Catter's and that he should stop. Tell him that his abomination of a boat for disabled folks, the Trapwing, or whatever name he's calling it these days, is overly complex, fraught with technical problems and substantially dangerous to the very kinds of people he says he is trying to address.

http://forums.sailinganarchy.com/index.php?showtopic=146245

 

See how far it gets you and report back as to how it goes.

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Doug has managed to chase more people out of open discussions of foils than a gang of litigation happy patent attorneys.

 

He has almost singlehandedly, made it much more difficult to find information about how to get into foiling moths by chasing them out of the Dinghy Anarchy forums despite lots of support from Clean and crew. Now one has to "get hooked up" before one can learn. That's a direct harm to the community.

 

you want it in multis? go ahead keep egging him on.

 

 

As I personally WANT to buy and sail a Mini- something Doug will never do, I resent his spamming his Fanboy idiocy across any forum that does not 100% rise up against him.

 

So Kampai - if you want to keep this RC forum for you and Lohring and Doug - persuade Doug to stay here and not go into any other forum

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... If the system works it will change small, high performance trimaran design for good...

 

It will do nothing of the kind. What a self-centered, preposterous pile of baloney.

 

Even if it does work, which is not a very high percentage play, it only proves that this particular application will work and has no bearing on other configurations, sizes, or purposes. It's an extreme one-off, so let's not get ahead ourselves on the counting of the chickens thing. A prudent, reasoned designer would never say this kind of thing long before they have a scale model in the water.

 

First thing that has to happen... Doug has to prove that he can actually complete a project and get it to work. Show it working on video for more than a split second at a real time playback and document the living crap out of the test with still photos from several angles. Well down the line somewhere in the very far away future, is a place where other thoughts MIGHT be on the table.

 

Pure, Fantasyland Hokum.

OK Chirs O, lets see some of your work then. If you are going to spend all this time slagging Doug and his ideas and attitude, lets at least be fair and have a look at what you have designed, built, and sailed....yourself please. your handle does say Small boat design, so I assume you have a portfolio of work to have a look at.

 

Normally we'd say "pics or it didn't happen" in this case it's "pics or shut the fuck up about Doug and his ideas". This thread was kind of pleasant until you came along, so show some boat porn born of your hands or go fuck yourself into some other thread and leave the model boat fans alone to play in peace.

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Chris has posted his work before.

 

Note how "well designed" the piece of work that Doug offers is:


  • His work is sketched on white paper that doesn't even use grids - and he only seems to have 3 drawings
  • He then posts OTHER PEOPLE'S CAD work as though it is his own

please.

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OK Chirs O, lets see some of your work then. If you are going to spend all this time slagging Doug and his ideas and attitude, lets at least be fair and have a look at what you have designed, built, and sailed....yourself please. your handle does say Small boat design, so I assume you have a portfolio of work to have a look at.

 

Blunted... My work is all over the place if you took but a second, or two, to avail yourself of the power of Google before you opened your trap.

 

Last year, one of my boats won its class in the Everglades Challenge in an extremely tough weather and sea state year and it was being sailed by a husband and wife team with little sailing experience. They even took it through the optional, Everglades National Park section of the course. I have completed boats on every continent on the planet save for Antarctica. I have designs for multihulls (cats and tris, as well as a high performance beach tri) monohulls, human powered vessels for paddle, pedal and oar, power boats, high efficiency multihull cruisers, tripping canoes, 8 sea kayak models, kid's racing dinghies... all sorts of boats for all sorts of applications, at all sorts of lengths.

 

I even have two, unique designs for people to cross the Atlantic; one for the smallest boat in LOA that is designed for research and will surprise you as to its design configuration and one that gives the occupant an opportunity to do it while in Stasis with full auto-pilot functions. Of course, that last one is intended as light humor and a way to poke fun at the "tiniest boat to go across a major ocean" brigade. All together, there are over 60 different boats in my portfolio at present with designs in progress for five more.

 

I sell a dozen, or more, sets of plans every month, depending on time of year and I'm having a blast working with folks who are eager to fulfill their dreams out on the water... and it's not even my everyday job that I do for a living.

 

My boats are designed to be built in marine plywood, strip built in wood, and vertical strip built in foam, all with glass/epoxy, or carbon/epoxy laminates inside and out.

 

If you can't find them, then you aren't looking. But, I will send you a heaping package of designs for you to examine if you PM me with your email address.

 

Let's keep in mind that you are the guy who just told a new member that he had no right to speak his opinion, simply because you deemed his total number of posts to be insufficient. So, about that, "go fuck yourself into some other thread" order...?

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Actually I expressed my concern about the seeming number of alternate identity trolls who popped up having never weighed in on an AC conversation previously, suddenly they were experts alighted from the sky on their flaming chariots if only to shout from the roof tops, "I told you so". I did not question their right to speak per se it was more questioning their troll-I-ness.

 

My point to you was that you have been in a multi-year pissing match with Doug, this was a nice thread until you showed up and got it all off on another tangent. If you have a hate on for Doug, fine have a hate on for him but try not to pollute a perfectly decent thread. If you are so fantastic with the design thing and crush Doug with YOUR ideas, show em. If there is one thing Doug HAS done, it's build a few bloody models and even sail them. True, it would better if there was less talk and more rock, E.g. Doug, shut up and finish the dam model already but until then, he has done one or two things. Granted you have done many more, congratulations, that's cool, so why not show them?

 

I am not suggesting you are wrong in respect of Doug's comments, he does take shit out of context and bend truth, but he also builds stuff. For my part, I have a lot more respect for a guy who builds stuff and tries new ideas, even if they're not great ideas then I do for someone who just knocks the other guy constantly. It's just a bummer when you spend all your time dumping on the guy even if he is wrong. For god's sake, a model boat forum, how much LESS consequential could it be, yet you make that the place to slap each other in the face with your dicks?

 

sounds like you are doing a nice business with your work, that's cool. I just wanted to see some pretty pictures of your stuff, especially if you have some stuff which might include say, foilers.....I suppose not, as you have made clear, it's not really your thing.

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Blunted,

 

There is a huge difference between some pretty little renderings, and actual boat design.

 

Several years ago, I tried contacting Mr. Chris Ostlind, as I was interested in possibly purchasing a set of plans. As soon as I started asking the type of questions prospective builders should ask, he became very agressive, demeaning and insulting.

 

Here is a perfect example of how Mr. Chris Ostlind responds to people looking for information on his designs:

 

http://www.boatdesign.net/forums/multihulls/chris-ostlind-lunadadesigns-anyone-built-their-plans-31066.html

 

Doesn't exactly take a rocket scientist to figure out who Paul B. is, does it. ;-)

 

***R. Thompson***

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I am not suggesting you are wrong in respect of Doug's comments, he does take shit out of context and bend truth, but he also builds stuff.

He does??? When? Back in the 1980s perhaps. But he's now taken 3 years to build a fairly simple RC trimaran. and its not done yet and he didn't even do all of the work himself.

 

He's proposed his "trapwing" dinghy for 5+ years now, and when I explained to him how he could build a full scale POC, he insisted that wasn't good enough that he needed the $$ to have SOMEONE ELSE build a full scale production prototype the first time out and until he could afford that, he wasn't going to build anything.

 

When he was talking about the "people's foiler" I put together a bunch of SA folks who were willing to each chip in cash so that Doug could travel from Cocoa Beach to the east coast location (South CA if I recollect) so that he could see real working foilers in actoon.... and he refused to take up the offer.

 

In fact Doug DOES NOT build things even though he says he does. That is precisely the problem all the stuff he is pointing to (except for this RC model that has been 3 years in the building in part at least by others) was built so far in the past, that it really isn't relevant. But Doug keeps flogging it as something new and ffolks like you buy into it.

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Actually I expressed my concern about the seeming number of alternate identity trolls who popped up having never weighed in on an AC conversation previously, suddenly they were experts alighted from the sky on their flaming chariots if only to shout from the roof tops, "I told you so". I did not question their right to speak per se it was more questioning their troll-I-ness.

 

My point to you was that you have been in a multi-year pissing match with Doug, this was a nice thread until you showed up and got it all off on another tangent. If you have a hate on for Doug, fine have a hate on for him but try not to pollute a perfectly decent thread. If you are so fantastic with the design thing and crush Doug with YOUR ideas, show em. If there is one thing Doug HAS done, it's build a few bloody models and even sail them. True, it would better if there was less talk and more rock, E.g. Doug, shut up and finish the dam model already but until then, he has done one or two things. Granted you have done many more, congratulations, that's cool, so why not show them?

 

I am not suggesting you are wrong in respect of Doug's comments, he does take shit out of context and bend truth, but he also builds stuff. For my part, I have a lot more respect for a guy who builds stuff and tries new ideas, even if they're not great ideas then I do for someone who just knocks the other guy constantly. It's just a bummer when you spend all your time dumping on the guy even if he is wrong. For god's sake, a model boat forum, how much LESS consequential could it be, yet you make that the place to slap each other in the face with your dicks?

 

sounds like you are doing a nice business with your work, that's cool. I just wanted to see some pretty pictures of your stuff, especially if you have some stuff which might include say, foilers.....I suppose not, as you have made clear, it's not really your thing.

 

I'm not going to refresh the bit regarding the AC Anarchy thread, Let's Put a Fork In Them. I made my point and I accept the explanation. Moving on.

 

Doug builds stuff? That's the position that justifies his incessant nonsense? I've been near this guy for going on ten years now and this model in question is the only thing he has built of any consequence in all that time. A model, mind you that my 23 yr. old, art student son, who is not interested in boat building at all, could have built in a matter of weeks, not years, as Doug has taken. Also, keep in mind that this is supposed to be Doug's big expression at this point in his life. Yet, for some undisclosed reason, it's taking THREE YEARS to build the damn thing. Lots of noise and posting, but little-to-no results. Still, the boat just sits there, as if it is a testament to brilliance in some way. About all I can attach right now to that function is that it's a pile of theory and not functionality.

 

"If there is one thing Doug HAS done, it's build a few bloody models and even sail them." Well, sure, if you also consider that the real model building to which you allude was done many, many years ago... as in a decade+ ago, but who's counting? I hit homeruns in American Legion ball once, so does that make me relevant at the plate today? Not on your life. That was then, this is now. Maybe you feel that the upcoming C's are a place where you can just stroll on out there and puff up your chest and not have to get it on... I would suggest otherwise and I suspect that you know this without being told. You are only as good as what you throw-down at any given moment. This, past laurels, thing is over-rated fluff and only good for the record books and comfy memories.

 

What I'm seeing here is a guy who isn't that motivated to complete his dream, is instead filling the bandwidth with a litany of droll postings with yet another list of objectives and such. Frankly, Blunted, it got so tiring that I had to say something, much like you felt that you had to say something about your troll issue on the AC forum. Mr. Lord flits from one topic to another, disturbing the flow of what was otherwise a pleasant experience on that thread and generally telling the guys who ARE out sailing these boats that they are full of shit (just like he did with the Mothies). At some point, the issue has to be pressed in order to restore a measure of interpersonal respect.

 

Go look at Doug's latest foray into how he demonstrates his mastery of all things foily on the, New Stuff in the A-Class and Curved-Foils threads. There, he tells Simon N, who is engaged in a thoughtful, serious test of all kinds of foil setups, placements, adjustments, etc., in order to discover the best kind of arrangement for his boat, along with a band of his mates, that basically, he's full of shit. Simon is out there, testing and then testing some more. Doug, by comparison, is plopped-down at a computer fussing about his post total and how much crap he can toss at the wall to obliterate the fact that, as you say, "he does take shit out of context and bend truth". One is working and one is slobbering... and the slobbering one is telling them that they don't know what they are talking about. Somewhere, the Mothies are laughing their asses off.

 

Everyone has their methodology for restoring order. Me, I'm willing to risk some of my earned credit on these pages in order to try to get Lord to cool his jets and become a decent citizen. I suspect that it's a fruitless effort, but I tried to get there, nevertheless. Some folks can't be reached with a message of reason. They resent being adjusted so much that they go out of their way to be repugnant. Douglas has a history of that kind of repugnance. Ask the Moth community. Ask the guys in the A-Class who refuse to participate here. How many more important groups of sailors must we see disgusted and turned away before there is a process for toning down the relentless fluff machine?

 

Lastly... there is a constant stream of fresh faces here. Some have great knowledge and some have next to none. I don't suspect that I can write any cautionary message for the knowledgeable guys and I prefer to deal with it in that fashion. But, the true newbies to sailing and/or this forum, could easily buy into Doug's blather and think that he's the cat's piss when it comes to substantive ideas. Since one of my objectives in all this effort involved with boat design and building is aimed at encouraging good folks to have a blast out on the water, I do feel that it's one of my responsibilities to help these guys sort this mess enough to find their way through the BS thicket. I'm not a soldier, not a crusader, not looking for commendations and I'm not perfect... just attempting to help those who are new to get a shot at solid information that is grounded and valuable, as opposed to the hype machine message that has routinely said... none of that matters, just fly to the frivolous, ill-advised segment and get your thrill there, even when it is poorly conceived and executed... and I'm not talking about foiling as a development in sailing in the broader context. I'm perfectly fine with foiling as an application. I just don't see it as functional for recreational and cruising sailors.

 

This sport is tanking badly in the big mix of recreational pursuits available to the mass of people out there who MIGHT have an interest. Sailing now represents 3% of the overall boating marketplace with charted sales volume on a steady decline for the past ten years. If we don't want it to wind-down to the barest trickle, which will ultimately be a very bad thing for our sport, then we have to get all kinds of small issues resolved before it is but a memory. Driving away exciting sailing components, such as Moths and A-Cats, from one of the main forum sites on the web is one of the distinct process elements for continued failure of the sailing world in the eyes of new participants.

 

You guys can, of course, do what you want. I've made my attempt at something like reason on these pages. Blunted, I wish you the best in your upcoming efforts.

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Here are three pictures of the hulls with the Hydroturf installed. This stuff didn't add significant weight but I think it adds to the appearance and on the full size boat provides traction. This is an exact(for the most part, except foil T/C and section-area is scale) scale model of an 18' tri over 22' wide. Also the pictures show the center portion of the crossarms painted black . And you may be able to see the wand mounting system with the inset carbon plates for the main foil(just ahead of the forward cross on the main hull). This boat uses dual wands which will maintain altitude at between 10-13 degrees, nominally, but the system can be "turned off" and flown manually with all the advantages the unique foil system can provide.

Doug, why did you add that stuff to the model? Isn't it just adding excess weight? Is it scaled to the proper thickness? Nobody is going to be on this thing, why spend the time and $ on it? I am beginning to think (actually getting pretty sure of it) that this whole project is about the model, that's as far as it will go and as far as you ever intended to go.

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yeah I get Doug. However most models that are used for this sort of thing have markings and such all over them so photos can be analyzed precisly. The fluff is left off. The way you are moving forward it looks to me like the model is the final destination. Don't get me wrong, it's cool looking and all and I hope it does what you are hoping for. Btw is starting to look like a Klingon Bird of Prey with a snazzy paint job.

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... starting to look like a Klingon Bird of Prey...

 

+10

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More Fire Arrow MPX Test Model:

--LOA 5.5'+gantry

--BEAM- 7'

--Wing Mast Length- 90"

--SA-3182 sq.in(squaretop jib +square top main)

--Predicted takeoff speed to fly the main hull-5mph

--Weight-about 15.5-16.5lb.

doug isn't 15-16 pounds kinda heavy? I forget, this thing doesn't have ballast does it?

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hmm 3.33"/foot ok so that's roughly 1/4 scale. And we know that volume/material increases as the square of that. so 16x.

 

so that means at full scale its 288# which is 130kg roughly. vs say a Weta at 96kg???? hmm so we have something that weighs 135% of a similar boat already in the marketplace.

 

And this supposed 18'er... IS NOT GOING TO BE BUILT.... because as Doug admits, he doesn't have the cash to do so. Nothing inherently wrong with that. But what IS wrong then is pretending that this boat "IS AN 18 FOOT" boat rather than just a big RC model.

 

 

uhuh... and then he's gonna spend 3 mos going on about the Trapwing. And say it isn't doable now - and then back to the 18'er but now we need a redesign... and back and forth and back and forth.

 

 

DOUG- just be honest. You are not going to build full size boats. you ONLY build RC boats. Nothing wrong with that. but it does mean you are not qualified to claim you have any experience designing or building for anything but RC boats

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hmm 3.33"/foot ok so that's roughly 1/4 scale. And we know that volume/material increases as the square of that. so 16x.

 

so that means at full scale its 288# which is 130kg roughly. vs say a Weta at 96kg???? hmm so we have something that weighs 135% of a similar boat already in the marketplace.

 

And this supposed 18'er... IS NOT GOING TO BE BUILT.... because as Doug admits, he doesn't have the cash to do so. Nothing inherently wrong with that. But what IS wrong then is pretending that this boat "IS AN 18 FOOT" boat rather than just a big RC model.

 

 

uhuh... and then he's gonna spend 3 mos going on about the Trapwing. And say it isn't doable now - and then back to the 18'er but now we need a redesign... and back and forth and back and forth.

 

 

DOUG- just be honest. You are not going to build full size boats. you ONLY build RC boats. Nothing wrong with that. but it does mean you are not qualified to claim you have any experience designing or building for anything but RC boats

For chrissakes BB - get the pickle out of your ass and enjoy the weekend -

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I'm stuck in russia for the weekend and haven't been sailing in 3 weeks.... Then I have to listen to Douug bullshit about how this is an 18' tri... but if we scale the numbers it weights 135% of a Weta and 150% of a 49er skiff.

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Hey Doug,

 

the boat looks really cool, whatever the performace will be - I find it inspiring and very well built. What's your clue about the good light wind performance while the main hull bottom is so flat. Doesn't that increase wetted surface and increases drag at light wind??

 

Some news from my workshop. I scaled down a MOD70 to the Mini40 rules. It will be a semiscale version still sailing good but inteded to look much better than the regular mini40 boats. I added some volume to the hulls according to scale, should be sailing this summer.

 

Cheers,

 

Chris

post-51057-0-54676700-1370205682_thumb.jpg

post-51057-0-43291800-1370205733_thumb.jpg

post-51057-0-52389700-1370205796_thumb.jpg

post-51057-0-52452900-1370205831_thumb.jpg

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...But there is another potential benefit in tough conditions: the main hull will be much better in resisting a pitchpole than would a normal main hull....

 

 

That's not even close to the truth. A slender vaka hull will shed water more quickly, thus representing a more recoverable form should the bow bury, for any reason. A broad, nearly flat surface, such as the one that we see in your scale model, will provide a high degree of resistance to the shedding function and allow the pitching moment from the sails to drive the boat over its nose when buried. This is multihull design 101.

 

Additionally, fairings on the akas are irrelevant for this model... just pure fluff that will offer no substantive benefit compared to the added weight. There's enough aero drag stuff on this boat already that any kind of attempt to reduce drag should begin with the unneeded stuff... not the least of which are the vertical tubes for the aka supports, the exposed aka tubes across the vaka hull, the curved, end of aka, forms and even those unnecessary grip pads... all of that stuff adds drag and if you are serious about the design being sleek, you'll get rid of it and find better solutions.

 

"Simplicate and add more lightness" - William Bushnell Stout

 

Stout is remembered for his Farberistic engineering credo, "Simplicate and add more lightness." This would later become best known as the adopted maxim of Colin Chapman of Lotus Cars. It actually originated with Stout's designer Gordon Hooton... from Wikipedia page regarding Stout.

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Nor Doug is this a "scale model of an 18' boat" You yourself have admitted you don't actually have any drawings or engineering designs of the 18' version. Now we find that you opted for this funky vaka shape is so that you could possibly re-use the 25+yo hull of your old "foiler" that was an abject failure back then. So please, stop saying its a "scale model" of something when that something does not exist.

 

Now as to the flat hull shape -not only is there the issue that the higher drag shape in the bow will actually INCREASE pitchpoling in the case of coming off the foil, it also ignores the fact that flat does not mean more volume, particularly when there isn't much volume above the static WL as your hull lacks. Essentially this form acts as a spoon that will dig into the surface in the case of an near pitchpole.

 

Lasttly - and this is where you once again don't seem to understand the scaling issues from models to full sized boats: in the real world, the ideal hull flying is with the Vaka barely above the waves (most power out of the sails). But with a flat high-drag hull as your design has, waves will be a serious problem for that hull.

 

 

Its a funky looking model - which means that as models go - its likely to be a lot of fun on a pond. But it is neither a "scale" or a "design" model. Please stop misrepresenting it as such

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Hey Doug,

 

the boat looks really cool, whatever the performace will be - I find it inspiring and very well built. What's your clue about the good light wind performance while the main hull bottom is so flat. Doesn't that increase wetted surface and increases drag at light wind??

 

Some news from my workshop. I scaled down a MOD70 to the Mini40 rules. It will be a semiscale version still sailing good but inteded to look much better than the regular mini40 boats. I added some volume to the hulls according to scale, should be sailing this summer.

 

Cheers,

 

Chris

Nice quality work Kampai.

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Doug, I don't care what scale issues you want to fiddle with, this vaka hull is a lousy form study for a multihull shape if you expect it to resist pitchpoling. Oh, you can tool around sedately in flat water and light airs and not risk anything, but the second that you try to light it up and there is a chop, or waves present, this thing is going over its nose and that's the end of the test.

 

You have a wave piercing bow and immediately the shape flattens and widens extremely quickly. Only the tiniest of waves will wash off this broad deck shape. Anything with force, size and water mass and you will have cooked the goose in a big way. Why you insist on thinking that this shape is a good one for the suggested task is beyond me. Just look at all the scale models arrayed in photos in the postings prior to this one. Do you see anything there that would suggest that a wide flat deck is a successful design solution? You have completely missed the whole design study function of how a wave piercing form behaves and must be shaped to be successful.

 

Perhaps Kampai can step in here and offer some counsel on this matter?

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so I think we all need to step back a bit and let Doug do his thing. Constant attack isn't necessary. Doug, if you quote me as saying this means I approve of your design I'll jump all over that.

 

I am curious though, since you are admitting you already have the center hull, then why didn't you just build it full sized? Many people offered you advice on how to get going on the cheap and now it seems you could have gone even cheaper. Why not build it full sized? Seems you are scaling down to test what you are going to have to scale up? Eats up funds quick.

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400# dry weight!!!! WOW!! I knew I was being generous when I estimated it a 2x a normal skiff of that size but 400#? Add in crew and it is 600#. Holy catastrophe, that's 1/4 the dry weight of a J-24.

 

that said Chris, the model boat will sail just fine. This is a great example of one of the things that does not scale well from models to full size precisely because of the difference in Reynolds numbers. Was talking to a NASA engineer this last week (the guy who lead the team that developed the recently announced inflatable heat shield) . He was describing a project of trying to build models of 757s to train pilots. And the problem they had was that because of the reynolds diffs, they could not scale the throw surfaces properly.

 

so this thing will sail fine as a model, but will never be full scale. Doug you yourself admitted you cannot afford to build the full sized boat. hence this is not a SCALE model, since it is not being scaled down from anything. It is simply A MODEL.

 

Own that and enjoy it.

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so I think we all need to step back a bit and let Doug do his thing. Constant attack isn't necessary. Doug, if you quote me as saying this means I approve of your design I'll jump all over that.

 

I am curious though, since you are admitting you already have the center hull, then why didn't you just build it full sized? Many people offered you advice on how to get going on the cheap and now it seems you could have gone even cheaper. Why not build it full sized? Seems you are scaling down to test what you are going to have to scale up? Eats up funds quick.

"admitting"??!! Geez, I've talked about the full size hull since close to my first post both here and on boat design.

Second answer: money-model testing saves time and money.

 

no it doesn't. not when you have 1/2 the hulls built already! Plus how is 2+ years saving time? I think I am done on this one....

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several models over 10 years, blah, blah,blah. That's just the model. Then you have to get the 14 footer up to speed, then you will move onto the 18 footer. By then most of the posters in this thread will be in nursing homes. Doug, you are older than me by, I am guessing here, 10 years. Get on with it. Time is short.

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somewhere vaguely I remember Doug being around 68 right now

 

The advantage of never actually building a full sized boat is that the "idea" never risks being proven wrong. Failures at the model level can always be attributed to the inability of certain forces and parameters (reynolds number) from scaling linearly

 

But 400# for an 18' boat... Holy Catastrophe!!!

 

That's what a Hobie F18 weighs and that's not known for its light weight. An ACat weighs 1/2 that for the same length.

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What's the science behind the curved horizontal foil? I know that this is what the kiwi's board looks like, but why is it better than having a straight horizontal part?

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Doug thanks for the link to Valenza's analysis. Its interesting and clever.

 

It also really shows you don't understand a word of it given you now thrice modified pictures:

 

http://forums.sailinganarchy.com/index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=193789

 

you confuse an S board with a curved board. And your diagram of where the "primary lift area is" for your particular board is frankly just wrong, the "L" generates as much if not more lift than the curved area. On Valenzas analysis the notion of ride control is essentially a combination of the diagonal surface piercing foils of l'hydroptere blended into two vertical sections: one above for insertion into the DB trunk and one below for lateral resistance/lift

Your "design" does not do that.


BTW a hint for manufacturability:

 

You would be much better off pushing in metal (or CF battens from a kite if you prefer) spars, then cutting the foam into pieces where the run is relatively straight. tack glue a metal or plywood template of the foil section you want to use to each end, and the either hotwire cut or longboard sand the subsection of foam.

 

When done, reinsert the spars to align the foam blocks and reglue the blocks together. Do some final fairing and then cover.

 

Butt as you have the plugs cut now, you really need a 5 axis CNC machine to get them right

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Ohh please doug , the area labled in yellow is tagged by you as " primary lift area of surface piercing foil"... your own damn diagram.. And you added that diagram AFTER adding Valenza's analysis not before so you are being dishonest in the timeline.

And since you offer it as an explanation of why your foils are curved the way they are, its rather silly.

 

and you can thank me later for the manufacturability advice

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Interesting that "Daiquiri" (Slavi) over at Boatdesign.net is asking a very similar question as to how the foil section is going to be included in the snappy-fresh Styrofoam blocks... which have no lifting section shape at all. Since there's no, real easy way to hand shape these blocks with an accurate section applied, I see this as a multi-axis, CNC router job... and more delays due to an overly complex design. Failure to construct with a seriously accurate section, chord and span could harm the capacity for the boat to perform as intended, so precision fabricating is a real issue at this point.

 

Here's the post from early this morning at BD.net http://www.boatdesign.net/forums/multihulls/high-performance-mpx-foil-self-righting-trimaran-test-model-36058-29.html

 

Engineering and Design

 

Join Date: May 2004
Rep: 2989 Posts: 3,584
Location: Italy (Garda Lake) and Croatia (Istria)
Doug,
How do you intend to carve the styro block to the exact shape of the airfoil sections?

 

 

 

One of the amusing aspects of all this, is that all along, Douglas has always tried to tell everyone that fabricating lifting foils for flying was just as easy and cheap as building straight daggerboards. Clearly, it is not.

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Chris its not that hard. you do the same thing as you would with a lost wax clay casting. you cut it up and then glue it back together. Since the core doesn't carry any strength except slightly in sheer, using multiple shaping "ribs" isn't a bad solution.

 

So you poke 4 CF rods (from a kite shop) into the foil and cut it chordwise into sections that are pretty much straight. (with the funky curves on this thing that's potentially as many as 6 or 8 pieces) you then cut two ribs that are aligned on the rods. Take each section, tack glue (white glue so you can dissolve it with water) to each end of the foam block. shape with a long board. Glue the pieces together.

 

I've done it with some RC airplane wings, and Epoxyworks has some other folks doing similar things with compound curved objects sans 5 axis CNC. It slow and a PITA but its doable.

 

Once sanded, reassemble on the tubes and glue it all together with 205. hit it with a final hand fair touchup and you are ready to lay up the surface.

 

 

that said, if I were doing this, I'd go out and buy myself a Fab@Home 3D printer (http://www.fabathome.org/index.php?q=node/10 Anothe kit promises to be $500 http://www.geek.com/gadgets/printrbot-an-all-in-one-3d-printer-kit-for-499-1442719/) and use that to build the core

 

Or the cheap way is to sign up for a TechShop membership http://www.techshop.ws/3_D_Printing.html

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Fabulous posting by Lord today at bd.net showing the teensy little templates he's going to use to shape the foils for his model. Now, ordinarily, I'd be all for a template session for a full-sized, cored daggerboard/rudder, as very good shapes can be had if someone is really good at 3D sculptural technique and has good sensation in their finger tips to feel for irregularities.

 

The problem for boards this small with very specific surface requirements, as we see in these teeny little lifting foils, is... surface irregularities are scaled as much bigger discrepancies as one sizes down, putting an even greater demand on foil accuracy... if one really cares about lift efficiency of the suggested foil. The smaller you go, the more precise the foil needs to be in order to retain as much of the chosen section's capability. All this hassle with carbon tubes, carbon hull wrapping, carbon rudder gantry, etc. and the whole thing is being tossed to the wind with non-precision, hand shaped foils that have a highly malleable base from which they are being cast. Seems totally backwards in priorities to me, but hey, it's only a three-year-in-the-making model, so who really cares if it works?

 

Sheesh

 

.

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Probable the best way to have gone with this is what some of the moth guys did. The found a shop that had a 3-axis wood CNC machine (actually I think they built it themselves http://buildyourcnc.com/ ) which they then used to mill out partwise foil molds out of MDF. They they then sealed the MDF surface with resin and then lots of mold release followed by a final layer of McLube. they were one shot molds, but they worked http://www.teknologika.com/mothblog/category/foil-construction/page/4/

 

this would result in a much nicer foil

 

 

 

 

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Hey Chris O,

why do you think these foils cannot be done accurately enough? Is it from practical experience or just guessing......?

There are plenty of working examples that those shapes can be sanded by hand precisely. Many RC sailors do it for ruders, etc. and they are sailing fast enough! There's also another example for a curved model foil here

 

http://www.rc-network.de/forum/showthread.php/357334-AC45-im-Mini40-Format?p=2933823&viewfull=1#post2933823

 

Actually the boat is flying with it already. Still of course the more accurate the profile is the better. I like the idea of a 3D printed mold that would be refined by sanding afterwards. Should be a lowbrainer for someone who knows how to 3D design such things.

 

Good discussion here finally!

 

Cheers Chris

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I think Chris' point is that the smaller the foil the greater the issue of imperfection affecting performance. Which means that if you are creating complex compound curves, the ability to get the precision you need by hand is low. If your foil is fairly simple: an elliptical with some washout/washin or even a constant radius curve - you can do that by hand.

 

But as soon as you start going into compound curves (Doug's design has at least 3 different radiuses of curvature in them) your ability to build consistently shaped foils by hand rapidly goes down.

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Hey Chris O,

why do you think these foils cannot be done accurately enough? Is it from practical experience or just guessing......?

There are plenty of working examples that those shapes can be sanded by hand precisely. Many RC sailors do it for ruders, etc. and they are sailing fast enough! There's also another example for a curved model foil here

 

 

Actually the boat is flying with it already. Still of course the more accurate the profile is the better. I like the idea of a 3D printed mold that would be refined by sanding afterwards. Should be a lowbrainer for someone who knows how to 3D design such things.

 

Good discussion here finally!

 

Thanks for the comments, Chris.

 

You touched on my reasoning in your own post when you said, "Still of course the more accurate the profile is the better" I totally concur with this position and to further the point... I do not think that Doug's build technique is anywhere accurate enough to make a matching pair of foils of this type and size by hand, There will be gross imperfections in the individual lifting surfaces for each foil and they will not be precise mirror copies of one another. This will yield non-standard results when testing and draw all kinds of erroneous comparisons into the analysis function.

 

If the purpose of this boat is to evaluate the potential for a full-sized craft, and not simply enjoy the process of model building, then precision in design, build and testing regime is of the highest importance, or the data derived will be functionally unacceptable. If all one wants to do is get the function into a large arena of acceptability like, oh... a Futbol Pitch area, then I suppose that this approach is just fine. If it's about data for analysis and application to a larger, more expensive boat on which a human can be seated, then this business is so full of errors, it is less than acceptable.

 

There are guys over on the Curved Foils thread on these pages who are discussing how foil surface imperfections lead to loss of lift and foil efficiency, yet, here we have a proponent who is building his never-before-built, unknown, L-shaped micro foils in a haphazard fashion with no real ability to form repeatable shapes and sections and it's being touted over on bd.net in the following fashion: "...I have a jig for the shape and will use 80 and 220 grit sandpaper. I've successfully shaped many foils this way in the past-good enough for one off. "

 

So, how does one produce meaningful data from the completed project? This whole thing is about throwing material at a lot of guess work and then using said results (should it work at all) for a technical discussion that I would assume to support one's theories. At this rate, these foils won't support any theories. If there is one truly critical area of this design that demands real precision, it would be with these untried, guess work derived foils.

 

I'm just wondering if the foils for any of the AC boats are built in this fashion and if the aero-hydrodynamicists would accept these kinds of bits as functionally able to deliver meaningful analytical data? Draw your own conclusions, but I think that at this point in the build, one should be going, All-In with the accuracy function so that a group of solid knowns can be used as a baseline for analysis.

 

If this were basically a hobbyists expression of personal interest, then I understand how this methodology is being used for the lifting foils.

.

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Still no answer as to surface irregularity issues, foil matching port/starboard problems, or how the overall planform and component angles are verified as workable. Doug, I know guys who are lifelong pattern makers with precision objects and they do not make each half of a molded object exactly like each other. Yet, you say it's, "-good enough for one off"

 

So, let's get this right... Three years to build the hull and connective portions of the model (the easy part) and mere hours to make accurate foils (the hardest part of all) that will provide analytical data to substantiate the performance potential of a full-sized boat. Typical Doug Lord procedural process. Ignore the substantive issues and pretend that they don't apply... maybe they'll just go POOF! and disappear... kinda like the Aeroskiff.

 

Douglas... you spend inordinate amounts of time outlining the details and numerical values for the design at hand, coupled with reams of lists in post after post until everyone is bleary eyed, if they haven't already left the discussion due to boredom, THEN... you approach the most critical component of the entire project, the part on which, literally, the whole idea is riding, as if it's not worthy of a serious accurate representation. Then, you produce said complex, overly quantified objects as if they could be built correctly by any doofus in an 8th grade wood shop class.

 

It's certainly, shall we say.... amusing.

 

I'm just wondering as to why you are not sewing/gluing-up your own sail with the same haphazard approach? Or, spinning your own carbon mast, or, tubes... or painting your own boat. It would seem that a guy with this foil building approach should be able to do that stuff just as accurately... seeing as how you believe that accuracy is not that important.

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In RC model testing the only thing that matters is planform and T/C ratio according to no less an authority than Dr. Sam Bradfield. There is no attempt to test the foils at a specific Reynolds number-that is beyond the scope of this type of testing.

This method has a series of stages and at each stage fairing is taken one step better-it is a proven, quick and accurate method to build and test foils(but not foil section). The foil section and T/C ratio on these foils is based on some sections from David Hollom(for high speed models as best I remember them) and the sections used on the F3 adapted for this model. The sections are 3-6% thinner than they would be on a full size foil.

-----

The ama molds are shaped and only the daggerboard remains. Hopefully the molds will all be glassed by tonight. Then tomorrow or Thursday they'll all be laid up out of woven and uni carbon(plus carbon rods on the daggerboard)

uhuh... so you don't get any info on how well the foils work Righht

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I see various people active in RC boats with postings that are consistent with what Doug is doing and/or really are interested in his build.

 

I see people posting such that they sound like they think the know more about RC boats than Doug. However not one of them add "when I tried xxx with my RC build" to their discussions.

 

I am perfectly willing to tell Doug when his enthusiasm seems to be leading him to jump to conclusions not supported by real experience.

 

I am also fed up with the absolute trash talk from a bunch of jerks.

 

This is a RC boat thread. The anti-Doug crowd constantly point out that he talks bigger than he should where he does not have real experience. Go pound Doug in other threads if you must, but PLEASE show us that you have more experience in the world of RC boats than he has or just SHUT UP already!!!!!!.

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The objections do have substance. Which is a lot more than can be said for your rant.

 

What you are objecting to is a function of style, rather than substance. So noted, you don't care for the style.

 

What should be understood is that I never suggested that Doug Shut-Up, or to stop work. Apparently to you, all threads should be met with the same gushing enthusiasm as a teenage girl fawning over her new boyfriend, or I should take the objections elsewhere. You want Candyland and not what realities are existent. You want blind acceptance, rather than a balanced look at a project.

 

Lastly, Bubba... are you serious? Your arguing for a deferment to Doug's experience making models and don't have a word to say regarding this three, special years it has taken to build the dang thing? If Doug is so experienced with models, why wasn't this goofy thing completed in less than a year, tested and already moving on to second, or third, iterations? I take it that it's a matter of comfy convenience that you ignore that component of the experience reality? Instead of completion, what we have been getting is relentless, foaming at the mouth, sheets of superficial numbers going nowhere and more blah-blah-blah. Please, Flados, exercise some of that engineer's common sense.

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Only to add some practical RC-foiling-life to the current academical discussion.. ;-) Some pics of the shinobi with the old 30cm long foils with NACA 63410 profile. Meanwhile I built shorter 24cm long foils which surprisingly work much better. Same profile, same angle of attack, more (!!??) lift, more speed, better tacking ability. I guess the long foils (on the pics) just create too much drag. A shorter rudder will follow as well.

post-51057-0-13849400-1371022636_thumb.jpg

post-51057-0-15780000-1371022645_thumb.jpg

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This topic was started by Doug in 2008!!!!! Since then he has posted 102 times to this topic. I have posted 12. Since 2008 Doug has still not gotten his boat sailing. That's 5 years And people are bitching about us keeping his progress slow!

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...My personal opinion is that a fully submerged foil system with wand based altitude control is faster on models because it develops unlimited RM where the surface piercer is in about the same RM category as a "normal" tri (touchy). And the fully submerged wand based foiler seems much more resistant to pitchpole...

 

ZTH's recent comments as to when this thread began, prompted me to go back and read-through what had already been said. The quote above clearly shows Mr. Lord's interest in the topic more than four years ago. Kinda interesting that the current configuration of this model uses both types of foils with piercers being out on the amas, even though Doug, very clearly, does not think that they will provide much benefit compared to "normal" tri setups with no foils.

 

There was also a wonderful quote regarding the complexity and relative costs of using a moveable ballast system (as we see on another thread) but that will have to wait...

 

 

In the meantime, the dance continues.

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Late last night, our boy, Douglas had this to say over on bd.net... "Paul, you should know that the two people making derogatory comments on SA include chris ostlind-who has zero model building experience and "BB" whose only experience was when he was a kid-neither have designed and built an RC or full size foiler- much less foils..."

 

It's interesting that Douglas has seen fit to derogatorily comment on my model building experience when he doesn't have a clue as to what I have accomplished, or not. He's just blabbing out there in a vacuum. Fact of the matter is this, Dougie... I've built plenty of models in my day; aircraft, boats, rolling vehicles, a wide gamut and I do know what issues there are n the fabrication.

 

If you are so sensitive as to not fully understand that my comments are balanced criticism to the incessant, effervescent nonsense that comes out of your mug, then you need to take a few high quality design classes at the university level where you will learn, (well, maybe you won't learn, but it will be put in your face, anyway) that if you don't take a hard look at your work with a critical eye for improvement, then you will continue to make design and build choices in a faulty state.

 

Doug, you haven't offered one single explanation as to how you deal with foils that are not matching pairs from side to side, or even addressed the fact that foils hand built in this fashion are not going to yield qualitative results for proper data analysis. You are simply flying by the seat of your pants after spending all sorts of cash, time and bandwidth on this project.

 

Daiquiri (Slavi) over on bd.net, says pretty much the same thing to you, just this morning...

 

"Doug, I would be curious to see how did you manage to guarantee the exact shape of the airfoils was reproduced on such a small scale. Did you have a hot wire bent and shaped to match the airfoil templates visible in your post #427?

The point is - you are certainly aware of the fact that foils are very sensitive to small changes to the chordwise distribution of thickness and camber. It is already painful to have it right on full scale, I can only imagine what it becomes at RC-model scales... eek.gif

If one cannot exactly reproduce (due to small scale and manufacturing method) the theoretical shape he desires, it might be less time consuming to use some simpler sections, perhaps optimized for manufacturing and not for hydrodynamic behavior?"

 

Yet, there you go, Doug, bumbling along like some toothless, out of shape, hillbilly who doesn't even know that peel ply doesn't follow curves in two different directions at the same time without needing to be darted. Looks like those fifty years of model building you claim, didn't teach you anything about the common materials in a composites shop.

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Doug, you don't know shite about what I did or did not build as a kid with one exception - that I said I built a foam cored wing based airplane in 3 mos rather than 3 years.

 

If you are going to trash talk folks, you might want to not do it behind their backs

 

P Flados - go ahead, support an asshole who is trash talking people in other forums without the consideration of confronting them directly. Just remember how that makes you look.

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